plat->phy_interface is unsigned integer, so the condition
can't be less than zero and the warning will never printed.
Fixes: 30bba69d7db4 ("stmmac: pci: Add dwmac support for Loongson")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
 {
        struct plat_stmmacenet_data *plat;
        struct stmmac_resources res;
-       bool mdio = false;
-       int ret, i;
        struct device_node *np;
+       int ret, i, phy_mode;
+       bool mdio = false;
 
        np = dev_of_node(&pdev->dev);
 
        if (plat->bus_id < 0)
                plat->bus_id = pci_dev_id(pdev);
 
-       plat->phy_interface = device_get_phy_mode(&pdev->dev);
-       if (plat->phy_interface < 0)
+       phy_mode = device_get_phy_mode(&pdev->dev);
+       if (phy_mode < 0)
                dev_err(&pdev->dev, "phy_mode not found\n");
 
+       plat->phy_interface = phy_mode;
        plat->interface = PHY_INTERFACE_MODE_GMII;
 
        pci_set_master(pdev);